1. Field of the Invention
The present invention relates to a covering for microtitration plates that are, in particular, applicable to PCR procedures.
2. Description of Related Art
Depending on their formats, conventional microtitration plates comprise defined numbers of wells that are used as reaction receptacles for receiving liquid specimens.
Microtitration plates are widely used for simultaneously treating different specimens in PCR procedures. In the course of PCR, the microtitration plate is inserted into a thermo-cycler wherein it is repeatedly heated and cooled. As a result, evaporation and condensation take place in the reaction receptacles. In order to avoid loss of liquid and any cross-contamination, the apertures of the reaction receptacles must be hermetically sealed during PCR.
It is known in this respect to mount flexible rubber mats on the microtitration plates. Sealing is implemented by applying pressure from above, for instance by means of a height-adjustable lid affixed to the cycler. Thereupon, the rubber mat under pressure will seal the reaction receptacle apertures. This design incurs the drawback that such flexible rubber mats are not easily handled in automated workstations.
The European patent document 1,142,795 describes sealing using a sealing mat fitted with a soft lower layer affixed to a rigid support plate. On account of the rigid feature of the support plate, such a covering may be handled in workstations. On the other hand the stratified feature of this covering is comparatively expensive.